The invention relates generally to antennas, and more particularly to extensible and retractable antennas.
The known prior art indicates that antenna deployment systems utilizing telescoping sections are known. In addition, cable and pulley systems are known which are adapted to extend and retract the telescoping sections. Although locking and releasing devices for telescoping sections are known, the prior art is deficient in teaching devices that are used to hold all the sections in the retracted or extended positions. Also, pyrotechnic and fluid operators are known to be utilized in such apparatus; however, limitations inherently exist in the environment of outer space when a deployable antenna system is utilized in connection with a spacecraft. Also inherent limitation exists in known prior art apparatus where smooth-acting and reliable operation is required in a restricted or confined space. Thus, there is a requirement for an antenna deployment system that is adapted to overcome the shortcomings of the prior art while providing simple, compact and efficient power means to deploy the antenna while preventing a premature return of the structure to the retracted position.
Accordingly, it is an object of the present invention to provide a new and improved system for deploying and retracting an antenna.
It is another object of the present invention to provide a simple, compact, smooth-acting and reliable means for deploying an antenna in an inaccessible environment.
It is yet another object to provide a relatively simple but reliable cam-operated mechanism for caging and releasing a retracted antenna.
Still another object of the invention is to provide an antenna deployment and retracting mechanism which effectively prevents premature retraction of the antenna.
Other objects and advantages of the invention will become apparent during the course of the following description.
Briefly, the above and other objectives are attained in the invention by the provision of a plurality of telescoping tubes which are nested one within the other when the antenna is retracted. The outermost tube can be rigidly attached to any stable support. The interior tubes of the structure are latched in the stowed or retracted position by a cam operated latch-release mechanism which cooperates with a dual motor driven cable drive for the antenna tube sections which includes a cable winding drum below the movable sections of the antenna to initiate antenna deployment by causing automatic release of the cam operated latch-release mechanism. The cable is terminated within a driving anchor means in the form of a tube at the base of the innermost and smallest telescoping tube section. A ratchet device on the cable winding drum prevents reverse rotation of the drum until the ratchet device is manually uncoupled from the drum.